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Cypella Herb. is one of the largest genera of Tigridieae (Iridaceae: Iridoideae) with more than 30 species accepted by the World Checklist of Iridaceae. The current infrageneric taxonomy rests exclusively on morphological characters, which are more or less reliable because of their intraspecific variability, and the delimitation of various species recently described remains obscure. Therefore, multiple lines of evidence were used to assess species boundaries in a morphologically conserved group of five species, including various populations of Cypella pusilla and the closely related C. gloriana. Phylogenetic analyses based on ten genetic markers (eight plastid and two nuclear loci) and multivariate analyses of 38 qualitative and quantitative phenotypic characters were performed. Results revealed that species-level diversity was overestimated and intraspecific morphological variability of C. pusilla underestimated. Overall, our findings support the utility of combining genetic evidence and broad morphological sampling to validate and describe species using complementary approaches. Consequently, an updated taxonomic treatment of C. pusilla is presented, including an expanded description of the species. [ABSTRACT FROM AUTHOR]

The polyploid species Herbertia lahue (Molina) Goldblatt is widespread in the grassland areas of southern America. In this study, genotypic and phenotypic variations among hexaploids and octoploids from H. lahue were assessed based on quantitative floral traits and ISSR markers. Additionally, gynoecium and breeding systems were analysed through anatomical analysis and hand-pollination experiments. Cytotypes are self-compatible, and the anatomy of the embryo sac remains similar in hexaploids and octoploids. AMOVA indicates that hexaploid populations are less genetically variable than octoploids (respectively 4 and 22 %, P < 0.001), thus the largest source of genetic variation for H. lahue lies among populations (82 %, P < 0.001), probably a combined effect of selfing, changes in population size, and local adaptation. Genetic variation between cytotypes was significant (16 %, P < 0.001), though unclear segregation among cytotypes was discovered through PCoA. A Mantel test indicated no relationship between geographic and genetic distances ( r = 0.04; P = 0.37), possibly as a result of the combined effect of the recurrent origin of polyploids, gene flow restricted by selfing, and poor capacity for seed dispersal. In terms of floral measurements, eight measures of perigonium, androecium, and gynoecium varied significantly between cytotypes, though no clear grouping was defined by PCA. Presumably, complex variation in floral characters across cytotypes may result in the absence of distinct grouping by PCA. The combined use of ISSR markers and morphological characters revealed a complex relationship between H. lahue cytotypes shaped by both intrinsic and extrinsic factors. [ABSTRACT FROM AUTHOR]

The main Korean mountain range that stretches from north to south (the Baekdudaegan) has been suggested to harbor an important glacial refugium for boreal and temperate plant species. Under this scenario, we expect high levels of within-population genetic variation and low or moderate degree of among-population differentiation within these species. To test this hypothesis, we examined clonal diversity and levels of allozyme diversity in the boreal Iris odaesanensis and in its temperate congener Iris rossii. In addition, we compiled data on boreal and temperate species whose distribution in the Korean Peninsula is mostly centered in the Baekdudaegan to determine if there is a common pattern. We found lower clonal diversity in I. odaesanensis compared to I. rossii. Both studied species maintained high levels of genetic variation as well as a moderate genetic differentiation ( %P = 52.5 and 47.5, A = 1.70 and 1.58, H = 0.158 and 0.150, and F = 0.196 and 0.189 for I. odaesanensis and I. rossii, respectively), in line with what occurs for the species distributed on the Baekdudaegan ( n = 14, %P = 46.7, A = 1.73, H = 0.161, and F = 0.190). This study strongly suggests that the Baekdudaegan may have acted as a refugium for boreal and temperate species, in a similar way to the southern Appalachians in the eastern United States. [ABSTRACT FROM AUTHOR]

In Croatia and the surrounding area, the genus Iris is represented with about 20 Alpine-Dinaric, Mediterranean and Pannonian taxa from the subgenera Iris and Limniris. We researched pollen morphology of all taxa by using scanning electron microscopy. All pollen grains are sulcate with few palynological features, which could have taxonomic importance on different classification levels: shape of dry pollen grains; shape, outline and approximate size of hydrated pollen grains, approximate size of the sulcus, and ornamentation of the sulcus membrane and of the exine. At least four pollen types were recognised and taxonomically delimited to the series level: two characterise the subgenus Iris, section Iris (series Elatae and Pumilae), and two the subgenus Limniris, section Limniris (series Laevigatae, Sibiricae and Spuriae). Taxonomic implications of pollen morphology of their critical groups and taxa have been evaluated. Possible phylogenetic implications of pollen morphology of the genus Iris on the Southern European area were suggested: the subgenus Iris is more advanced than the subgenus Limniris; I. graminea seems to be the most primitive member of the subgenus Limniris on the Southern European territory; and pollen morphology of the population of the subspecies I. sibirica subsp. erirrhiza from the Mountain Bjelolasica could represent a link between the subgenera Limniris and Iris in the territory of Southern Europe. The possible pathway of evolution of the genus Iris on the territory of Southern Europe was suggested: from the subgenus Limniris, through the 'linked taxon' I. sibirica subsp. erirrhiza from the Bjelolasica Mountain, to the subgenus Iris, series Pumilae, and finally to the series Elatae. [ABSTRACT FROM AUTHOR]

Zonneveld (Pl Syst Evol 281:217-245, ) proposed an infrageneric classification of Tulipa (Liliaceae) based on the nuclear content determined by flow cytometry and available morphological data. The nomenclatural consequences of this are discussed here, involving the typification of generic and infrageneric names. Additional notes on some species are given. Four subgenera are distinguished, of which two are new; ten sections are proposed, four new; three new combinations are made, and seven lectotypes are designated. Tulipa praecox Ten. is a later homonym of T. praecox Cav. (Descripcíon de las plantas. 2: 448, 625, ); its correct name is Tulipa agenensis DC. Tulipa lemmersii Zonn., A. Peterse, J. de Groot is validated here by giving the type citation. [ABSTRACT FROM AUTHOR]

Crocus antalyensis B. Mathew is a bulbous plant endemic to Turkey. It is morphologically variable within the western part of Anatolia. Amplified fragment length polymorphism (AFLP) marker system was used to detect genetic variation among the Crocus taxa. Twenty-two primer combinations were used to screen for polymorphism among the samples. Genetic variation ranged from 0.44 to 0.69. We demonstrated the efficiency of the AFLP marker system for discriminating between individual C. antalyensis specimens. A high level of genetic variation was present among C. antalyensis specimens collected from different locations in Turkey. We also observed that C. antalyensis subspp. are genetically distinct from their relative Crocus flavus Haw. subsp. dissectus Baytop & B. Mathew. A new subspecies of C. antalyensis B. Mathew from southern Turkey is described. It is characterized by striped outer perianth segments, waist-shaped flowers, and glabrous throat of the perianth. A composite image of the new subspecies is presented. [ABSTRACT FROM AUTHOR]

Sporogenesis, gametogenesis, fertilization and embryogenesis of Iris mandshurica Maxim. were observed using the normal paraffin method. The results are as follows: the development of the anther wall following the dicotyledonous type consisting of four layers, the epidermis, the endothecium, one middle layer and the secretory tapetum. Fibrous thickenings develop in the endothecium when the anther is shed. Simultaneous cytokinesis during microsporogenesis results in a tetrahedral tetrad of microspores. Mature pollen grains are two-celled. The ovary is inferior and trilocular with axial placenta. The ovule is anatropous, bitegminous and crassinucellate. The archesporial cell below the nucellar epidermis undergoes periclinal division producing the primary parietal cell and the primary sporogenous cell. The primary parietal cell participates in the nucellar formation; the primary sporogenous cell differentiates directly as the megasporocyte. Successive cytokinesis in the megasporocyte usually produces the linear tetrad, and the chalazal megaspore of the tetrad develops into a Polygonum-type embryo sac. The fertilization mode is porogamy. The pollen tube enters into the embryo sac and discharges two sperm 16-20 h after pollination. The fertilization is the postmitotic type of syngamy. The first division of the zygote is transversal. Endosperm formation is of the nuclear type. The systematic significance of the embryological characters of I. mandshurica is discussed. [ABSTRACT FROM AUTHOR]

The subgenus Xiphium is one of the six infrageneric divisions of the genus Iris. Chromosome numbers of six of the seven Xiphium species are known. Here the aim was to infer genetic and phylogenetic relationships based on chromosome numbers, chromosome markers and plastid sequences. Chromosomal locations of 5S and 45S rDNA loci were determined in 19 populations of the 7 species by fluorescence in situ hybridization (FISH). Additionally, the trnL- trnF plastid spacer was sequenced and a phylogenetic analysis performed. Based on chromosome markers, subgenus Xiphium species were classified into four groups that differed in the number and locations of both types of nrDNA: (1) I. tingitana (2 n = 28), I. filifolia (2 n = 30, 34) and I. xiphium (2 n = 34), (2) I. juncea (2 n = 32) and I. boissieri (2 n = 36), (3) I. serotina (2 n = 34) and (4) I. latifolia (2 n = 42). Although the trnL- trnF phylogeny was not fully resolved, the sequence analysis showed a well-supported subgroup of I. filifolia, I. tingitana and I. xiphium, as well as I. juncea. FISH physical maps of the Iris subgenus Xiphium taxa are species dependent. I. filifolia, I. tingitana and I. xiphium are very closely related species and share cytogenetic characteristics. Disploidy appears to have been central in the evolution of this subgenus, given a series of chromosome numbers (2 n = 28, 30, 32, 34, 36, 42) and our phylogenetic results. Clear differences were found among European and African populations of I. filifolia. A different taxonomic treatment of I. filifolia is supported for populations on both sides of the Strait of Gibraltar. [ABSTRACT FROM AUTHOR]

Field studies of 13 of the estimated 17 species of the southern African geophytic genus Ferraria (Iridaceae: Iridoideae) identified four distinct pollination systems. Ferraria flowers are radially symmetric and cupped with a large, mostly pale or dull-colored perianth. Perigonal nectaries secrete hexose dominant (fructose and glucose) nectar. Most species are pollinated by Diptera of four families, apparently attracted by strong floral odors, mostly putrid or fermenting, but sometimes apparently sweet, and a large perianth mottled and edged with dark color. Concentrated sugary secretions are produced on the tepal claws that form a shallow floral cup. In contrast, flowers of F. ferrariola have a deep, narrow floral cup, a pale blue or yellow perianth, and a spicy scent and are pollinated by bees in the family Apidae, rewarded by nectar of moderate sugar concentration. Ferraria divaricata and F. variabilis have dull-colored, darkly speckled or streaked perianths and produce ample, highly dilute nectar pooled at the base of the floral cup and are pollinated by eumenid and masarine wasps (Vespidae). Lastly, F. uncinata has flowers with a narrow floral cup and dull violet tepals with brown margins. They are visited only by meloid and melyrid beetles. All pollen transfers from the anther of a Ferraria flower to an insect’s body are passive, regardless of pollinator. Pollen load analyses suggests that all pollinators show a high degree of faithfulness to Ferraria flowers. [ABSTRACT FROM AUTHOR]

A recent study in a natural grassland in Argentina revealed that grazing strongly reduced the available pollinators for a population of Cypella herbertii. Comparing grazed and fenced areas (exclosures) we tested the hypothesis that self-incompatibility would be selected against in a pollinator-poor environment leading to changes in breeding system. No differences in breeding system were found between populations from inside and outside exclosures. However, we detected: (i) C. herbertii clearly exhibits a mixed-mating system but has a remarkably low spontaneous fruit formation; (ii) this species though highly self-compatible expresses a significant decay at seed set stage when self-pollinated. We conclude that grazing impact on pollinators together with C. herbertii’s high dependence on pollinators should be considered when assessing the risk of extinction of this species. [ABSTRACT FROM AUTHOR]

The genome size and base composition of the triploid Crocus sativus and its two diploid most probable ancestors, C. cartwrightianus and C. thomasii, was investigated and compared inter- and intra-specifically by means of flow cytometry. There was little variation in C. sativus and little difference from C. cartwrightianus. Crocus thomasii was significantly different from the others. Crocus cartwrightianus is the most probable diploid ancestor of C. sativus. [ABSTRACT FROM AUTHOR]

Reaction norms were determined in two natural populations of the perennial plant Iris pumila from contrasting light conditions at two levels of photosynthetically active radiation (105 and 35 µmol m−2s−1). Seedlings developed from free-pollinated seed families sampled individually from 19 and 12 randomly selected clonal genotypes in an exposed and a shaded population respectively, were grown in a growth room using a mixed model nested factorial experimental design and scored for a number of phenological and morphological traits. Ambient light conditions significantly affected all of the juvenile traits measured. In both populations, relatively convergent norms of reactions were revealed for leaf appearance dates, as well as for leaf number, suggesting the importance of these traits for functional adjustment to prevailing light conditions. Reaction norms for morphological traits, however, were largely nonparallel, but although often crossing each other, a significant family-by-treatment interaction in the ANCOVAs performed was not detected for any of the traits measured, indicating a small amount of genetic variation for plasticity in these populations. The extent of plastic response to light availability was determined and expressed as an index that estimates the percentage change in a trait value from a high to a low light level. Evolutionary and ecological implications of the observed plastic variations are also discussed. [ABSTRACT FROM AUTHOR]

The peacock moraeas are South African geophytes with Iris-like flowers that are characterized by broad outer tepals with iridescent spots. Three of the seven species were studied and found to be exclusively visited and pollinated by beetles. The primary pollinators were hopliine ( Scarabaeidae) beetles in the genera Peritrichia, Monochelus, Anisonyx and Anisochelus. These beetles visit flowers for nectar, pollen and mating. Peritrichia rufotibialis was the primary pollinator of Moraea villosa, P. abdominalis was the primary pollinator of M. tulbaghensis, while Monochelus sp. nov. was the primary pollinator of the third species, M. neopavonia. High levels of fruit set attest to the effectiveness of these beetles as pollinators. Average fruit set ranged from 83.5 ± 34.8% ( M. villosa) to 97.2 ± 11.6% ( M. tulbaghensis). Average seed set in the various populations was more variable, but was also quite high, ranging from 77.3 ± 40.8 ( M. villosa) to 342.2 ± 115.0 ( M. neopavonia) seeds per capsule. Although hopliine beetles are abundant and diverse in southern Africa and commonly visit flowers, this is the first well-documented report of pollination by these beetles. [ABSTRACT FROM AUTHOR]

A guild of 20 late spring- and early summer-flowering species of Iridaceae, Geraniaceae and Orchidaceae is pollinated partly or exclusively by the long-proboscid fly Moegistorhynchus longirostris (Nemestrinidae). This large-bodied fly, active in late spring and early summer, has mouthparts 40–70 (∓90) mm long and forages for nectar from a variety of species. These plants share a suite of convergent floral features including a straight or weakly curved floral tube usually 50–70 mm long but sometimes to 90 mm, relatively short petals or tepal lobes coloured white, cream or salmon with reddish nectar guides, and often violet or red anthers and pollen. Flowers of most species with these characteristics are zygomorphic with the stamens either arcuate (most Iridaceae) or declinate ( Geraniaceae and some Iridaceae). The flowers are odourless and typically secrete large amounts of nectar of relatively constant sugar concentration, mostly 24–29%, with a high sucrose:hexose ratio. Guild members utilize five separate sites of pollen deposition on the body of the fly, typically utilizing different deposition sites when two or more co-occur, indicating strong selection to aviod pollen contamination. M. longirostris is restricted to the west coast of southern Africa and at least 8 species appear to depend exclusively on the insect for pollination. The remaining species in the guild are pollinated by one or both of the long-proboscid flies Philoliche gulosa and P. rostrata (Tabanidae) over other parts of their range. Species and races pollinated entirely by M. longirostris have longer floral tubes which makes nectar unavailable to other insects, including other species of long-proboscid fly. The only insect with mouthparts long enough to forage effectively on these long-tubed flowers is M. longirostris and this fly must be considered a keystone species in the ecosystems in which it occurs. [ABSTRACT FROM AUTHOR]

A molecular phylogeny of the family Iridaceae based on the plastid gene rps4 was obtained using both parsimony and distance methods. Thirty-four species were examined together with eight outgroup species. Results show that the Iridaceae are monophyletic, and that Isophysis is likely to be the earliest emerging genus. Subfamily Ixioideae plus the genera Aristea and Nivenia form a strongly supported clade. Within subfam. Iridoideae, the tribe Irideae includes the genus Bobartia (of disputed position), and the tribe Mariceae includes Cypella. The division of Iridoideae into tribes is consistent with their geographical distribution. [ABSTRACT FROM AUTHOR]

The variation in the maternal effects on a number of the early Iris pumila seedling traits expressed under high and low light levels in a growthroom was studied. A reciprocal crossing design was used for the establishment of 20 full-sib families. Each family consisted of two maternal groups differing only in genotype used as a seed parent. Maternal variation was estimated from the variance between maternal groups within sibships. Two parameters for maternal variation were computed: the maternal effects coefficient m and the coefficient of maternal variation CV. Maternal effects significantly accounted for the phenotypic variation in seed mass and most of the early seedling traits. Light conditions prevailing during the seedling development markedly influenced overall structure of maternal correlations. Implications of maternal correlations on the integration of juvenile phenotype have also been discussed. [ABSTRACT FROM AUTHOR]

The reproductive system was studied in Crocus genus ( Iridaceae) following intra- and interspecific pollination, by using light and scanning electron microscopy. The results suggest that the stigma-style tract of the Crocus pistil is a mere promoter of pollen tube growth, while intra- and interspecific discrimination of compatible and incompatible pollen occurs in the ovarian tract. Here, the transmitting tissue consists of special epidermal cells, whose granular or floccular secretions provide the selective medium for the growth of pollen tubes. The ovarian self-incompatibility (SI) is widespread within the genus, resulting in a partial or complete suppression of self-fertilization. Moreover, postzygotic SI mechanisms, as well as postzygotic mechanisms of unknown nature, seem to be recurrent and both are responsible for seed abortion. The interspecific ovarian incompatibility concerns only unrelated crosses; crosses between related fertile species succeed both in fertilization and seed-set. [ABSTRACT FROM AUTHOR]

Crocus cartwrightianus and C. cartwrightianus cv. albus pollen have been studied from structural and ultrastructural points of view and the germination assayed in vivo and in vitro. C. cartwrightianus pollen is regularly shaped and sized, has a low percentage of anomalous grains and has a high germination rate in vitro, while C. cartwrightianus cv. albus is less regularly shaped with some variation in size and has a high percentage of anomalous grains and a low germination percentage in vitro. Ultrastructural observations have revealed, in the pollen of both the taxa, the presence of a thin elongated vegetative nucleus and a generative cell surrounded by a thin membrane. However, C. cartwrightianus pollen shows a thicker intine, and C. cartwrightianus cv. albus shows numerous pollen germination anomalies which are in common with C. sativus. [ABSTRACT FROM AUTHOR]

Ovule fertilization and seed set were investigated in Crocus thomasii and Crocus vernus subsp. vernus, after different matings. The results gave evidence for a strict ovarian barrier in C. thomasii, which prevents self-fertilization either in self- or mixed- and double-pollination. In C. vernus the ovarian barrier to selfing is not so effective, but a further incompatibility reaction is expressed after self-fertilization resulting in a complete failure of embryogenesis. The implications of the present observations in respect to the mechanisms of pregamic- and postgamic rejection, indicate that a gametophytic system of self-incompatibility controls the ovule fertilization, and a not yet defined system of self-incompatibility controls embryogenesis. [ABSTRACT FROM AUTHOR]

Herkogamy and gynodioecy were studied in the Moroccan species of Romulea. Several types of herkogamy are shown to occur in the different species, with each type corresponding to a characteristic perianth size. The degree of differentiation between female and hermaphrodite morphs varies among the different gynodioecious species. Herkogamy is considered to have evolved prior to the development of the gynodioecious condition. An evolutionary interpretation is proposed based on the degree of herkogamy and of gynodioecy in the different species. [ABSTRACT FROM AUTHOR]

Leaf anatomy is described in 32 species of 16 genera of the New World tribe Tigridieae ( Iridaceae, Iridoideae), including examples from both subtribes Cipurinae and Tigridiinae. Both plicate (pleated) and foliated (with flanges, or keel extensions) leaf types occur in both subtribes. However, among Tigridiinae, foliated leaves are restricted to Tigridia and differ from the foliated leaves of Cipurinae in that they lack subepidermal marginal sclerenchyma, which is present in all the foliated species of Cipurinae. This indicates that the foliated leaf type has evolved at least twice in the tribe, since the plicate leaf, which most closely resembles the equitant leaf typical of Iridaceae, is probably plesiomorphic. [ABSTRACT FROM AUTHOR]

Outcross, self- and mixed pollinations were performed in Crocus vernus subsp. vernus, a species with bicellular pollen, dry stigmas and hollow style. No differences were noted among the above pollinations concerning the germination of pollen and the growth of pollen tubes until the top of ovary. Within 45 min after pollinations 62% of pollen grains germinated. Pollen tubes penetrated the papilla cuticle extending along the papilla wall; on entry into stigmatic lobes they continued growth in the stylar secretion to ovarian locules. Here, however, self-pollen tubes failed to reach or to enter the ovule micropyle; while pollen tubes from either outcross- or mixed pollinations grew until fertilizing ovules. These observations gave evidence of a self-incompatibility system in Crocus, which appeared to be neutralized by mentor effect. The ovary as site of incompatibility response is discussed. [ABSTRACT FROM AUTHOR]

Variation patterns in phenotypic plasticity and broad sense heritability of 26 characters were examined within and among closely adjacent habitats of the bearded iris, Iris pumila. It was found that I. pumila has considerable differentiation for phenotypic plasticity and genetic variation over short distances. An analysis of relationships between character differentiation and phenotypic plasticity suggests that they could have evolved independently. Possible mechanisms for maintaining local differentiation of the observed plastic and genetic variation are also discussed. [ABSTRACT FROM AUTHOR]

The embryology of Crocus thomasii is described. Male meiosis is of simultaneous type, and gives rise to starchy microspores which develop into lipoid pollen grains; these are two-celled and show a spinulate acolpate, abaculate exine lacking apertures. The tapetum is glandular and its cells become bi- or sometimes multinucleate. The ovule is anatropous and bitegmic; the inner integument forms the micropyle. Megasporogenesis is heteropolar with starch accumulation in the functional chalazal megaspore. Embryo sac development conforms to the Polygonum type. The endosperm development is nuclear. The embryo develops according to the Caryophyllad type. In the ripe seed it is differentiated and enveloped by a starchy cellular endosperm. The embryological characters observed strongly favour a close relation between C. thomasii and C. sativus. [ABSTRACT FROM AUTHOR]

Representative specimens of the European Gladiolus species (excl. G. palustris) were used to study variability and relationships. 25 characters were measured for cluster, principal component and Wells hybrid analyses (Figs. 1-3). Three (with PCA) respective five (cluster analysis) main groups are revealed. Bulb characteristics appear to be very useful for indentification. The subspecific status of G. communis subsp. byzantinus is confirmed. Hybrids of four different parental combinations were detected in our collection. Most species include polyploid series. Partly 3x, 4x, 6x, 8x, 12x and aneuploid cytotypes but no diploids were found. Polyploids as pioneers and hybridization of sympatric species are apparently linked to migrations during the glacial periods. [ABSTRACT FROM AUTHOR]

Individual flowers of Moraea inclinata are nectariferous and last about six hours. They appear to be pollinated largely by bees in the family Halictidae ( Lasioglossum spp., Nomia spp., Zonalictus) and to a lesser extent by bees in the family Anthophoridae ( Amegilla). The mechanism of bee-pollination in M. inclinata is the ' Iris type'; i.e., each flower consists of three pollination units (an outer tepal, a partly exserted anther, and the opposed style branch which terminates in a pair of petal-like crests). Bees rarely visit more than one pollination unit per flower. Transferral of pollen to the bee is passive and nototribic although all bees collected on the flowers were female and 55% of the bees carried pollen loads with 2-5 pollen taxa in their scopae. Moraea brevistyla flowers are nectariferous but lack scent and last two days. They are visited infrequently by bees and only one female Lasioglossum spec. carried the pollen of M. brevistyla. Unlike flowers of M. inclinata those of M. brevistyla deposit pollen only on the head and thorax. Bee-mediated autogamy in both species is avoided due to the erratic foraging patterns of the bees and the flexibility of each stigma lobe as the bee backs out of the flower. Approximately 2-4 flowers in the inflorescences of both species (6-8 flowers/infloresence) develop into capsules. [ABSTRACT FROM AUTHOR]

The problem of taxa equivalency in phylogenetically distant groups can hardly be solved by comparing morphological differences alone. An attempt is made to approach the problem by means of DNA comparisons, e.g., DNA hybridization. Data obtained for Compositae, Umbelliferae and Iridaceae indicate that both unique and repetitive DNA sequence comparisons lead to the conclusions that genera within these families are not equivalent, e.g., the differences in the DNA among the species of Iris are much more pronounced than among those of Achillea; some genera of Umbelliferae occupy an intermediate position. [ABSTRACT FROM AUTHOR]

Meiosis and mitosis are described in cultivated Crocus sativus of Iran. This indicates that this species is an autotriploid and sterile. Karyotype analysis, rare inversions, laggard chromosomes and distribution of chromosomes in the first anaphase are described, and the reasons for its sterility are given. [ABSTRACT FROM AUTHOR]

A detailed description of female reproductive structures in Crocus is given, using three different techniques: wax embedding and sectioning, SEM, and observation of cleared ovules by interference contrast microscopy. The results of this examination, and a chromosomal investigation of the intraspecific hybrids obtained by crossing specimens of C. speciosus of different karyotypes, are used to test the hypothesis that Crocus is apomictic. Although facultative diplospory cannot be entirely ruled out, it is suggested that apomixis is an unlikely explanation from the unusual amount of chromosomal variation found in some species of Crocus, and alternative causes are discussed. [ABSTRACT FROM AUTHOR]

Although the South American Iridaceae are cytologically diverse, three tribes are distinguishable on the basis of karyotype morphology. The Sisyrinchieae and Trimezieae have variable basic numbers, ploidy levels and chromosome sizes, while the Tigridieae are characterized by a relatively uniform basic number and bimodal karyotype. Changes in chromosome size within genera may suggest fluctuations in their DNA amount with latitude and altitude, particularly in Sisyrinchium. The results are considered in terms of opportunities for more detailed research. [ABSTRACT FROM AUTHOR]

Meiosis is described in thirty-seven taxa ranging from low to high chromosome numbers. Most were regular and bivalent forming. C. flavus subsp. flavus was observed at first anaphase only and was highly irregular. C. speciosus had one or two possible interchange quadrivalents and the C. vernus aneuploid cultivars exhibited multivalents, bivalents and univalents together with some anaphase bridges and fragments. Chiasma frequency is determined here for the first time. [ABSTRACT FROM AUTHOR]

Crocus speciosus is a widely distributed autumn-flowering species showing considerable variation in its morphological characters. Three subspecies are recognised, two of which are endemic to small areas of Turkey. The third, subsp. speciosus, occurs in a much wider area and contains a number of different cytotypes. C. pulchellus is a distinct but closely related species. The morphological relationships between the species and subspecies are discussed and a key to the taxa is provided. Cytological data are given and a distribution map of the cytotypes is provided. A detailed study of the leaf anatomy is presented. [ABSTRACT FROM AUTHOR]

Structure and behaviour of the underground organs of Iris vartani were investigated in connection with the vegetative reproduction of this species. Under favourable conditions, well developed mature plants give rise to two replacement bulbs and to several propagation bulblets each year. In spite of this considerable vegetative propagation, no crowding occurs at the natural habitat. Controlled experiments show that as soon as a small group is formed, each bulb produces only one replacement bulb and not two as before. Moreover, the bulblets do not sprout while they are attached to the respective mother bulbs, but rather die and disintegrate, remaining as empty peels. In contrast, detached bulblets, sown individually in separate pots, germinate readily. Consequently, the aggregates of I. vartani do not increase to any great extent and thus ensure their survival 'in situ' for many years. [ABSTRACT FROM AUTHOR]

Numerous Mediterranean geophytes are hysteranthous, i.e. they flower in a leafless stage during autumn. On the basis of their life cycles and other features two types can be recognized: In the Crocus type flowers with subterranean ovary develop at the start of the new reproductive cycle from an annual storage organ; seed dispersal and germination are delayed to the spring and the next autumn. In the Urginea type, flowers with supraterranean ovary originate from a perennial storage organ at the end of the life cycle; seed dispersal and germination follow flowering immediately. Similar rhythms exist in other seasonal climates. Field observations and some experiments demonstrate flower stimulation by temperature decrease or increase in different geophytes, and relationships between water supply and synanthous versus hysteranthous leaf development. The origin, ecological importance, and horticultural implication of the hysteranthous syndrome is discussed. [ABSTRACT FROM AUTHOR]

Basic chromosome number in Galaxia is believed to be x = 9, and this number, or multiples, occurs in all species of subgenus Galaxia. In subgenus Eurystigma, G. barnardii has n = 8, G. versicolor n = 8 and 7, G. citrina n = 8, 7 and 17 while G. variabilis has n = 7 exclusively. Karyotypes in forms of G. versicolor with n = 7 and in G. variabilis are quite different and clearly originated independently. Karyotypic features provide evidence for the hypothesis that changes in chromosome number were accomplished through chromosome fusion either by classical Robertsonian translocation, or unequal reciprocal translocation. [ABSTRACT FROM AUTHOR]

Chromosome counts and detailed karyotype analyses are presented for I. attica (2n = 16), and I. mellita and I. reichenbachii (both 2n = 24). Karyotypes differ in symmetry, number of telocentrics, occurrence of heteromorphic chromosome pairs, etc. For Western Anatolia first unequivocal records of I. attica and local differentiation of I. mellita are demonstrated. The Balkan and West-Ukrainian I. reichenbachii appears not to be indigenous to Anatolia. [ABSTRACT FROM AUTHOR]

The distribution of four variants for flower colour of Crocus scepusiensis in the northern part of the Western Carpathians is described. The frequency of white stigmata morphs declines from east to west. In the center of the area stigmata colour morphs show strikingly patchy distribution. White perianth morphs usually occur at low frequencies and their distribution with minor exceptions is restricted to the central part of the area, where patchy distribution of the morphs is a rule. These distribution patterns suggest that the founder effect has played a major role in determining the genetic composition of individual populations. The cline for stigmata colour may also be explained by the dynamics of population expansion. No influence of selection can be demonstrated, but the association between perianth and stigmata colour, and the excessively low frequency of white perianth morphs may imply that the polymorphisms are not selectively neutral. [ABSTRACT FROM AUTHOR]

Crocus corsicus, an endemic to Corsica has 2n = 18 chromosomes. C. minimus from Corsica and Sardinia has 2n = 24, but plants with 2n = 25, 26, 27, 28, 29 and 30, including a variable number of telocentric chromosomes, were found in some populations in south-eastern Corsica. A natural hybrid (2n = 22) between C. corsicus (2n = 18) and C. minimus (2n = 26) is reported. The relationship between the two species is discussed, and descriptions and a key are given. [ABSTRACT FROM AUTHOR]

Cytotypes of the Crocus vernus aggregate differ slightly in their seed surface patterns. Crocus albiflorus may be grouped together with Crocus vernus subsp. vernus, both are relatively easily distinguishable by their seed surface patterns from the Crocus scepusiensis-Crocus heuffelianus group. [ABSTRACT FROM AUTHOR]

Populations of C. cartwrightianus, C. hadriaticus and C. thomasii from the Balkans have 2n = 16 as has the Middle Eastern C. pallasii subsp. haussknechtii. C. dispathaceus and C. pallasii subsp. pallasii have 2n = 14 while C. pallasii subsp. turcicus has 2n = 12. C. niveus has 2n = 28 and C. sativus is an autotriploid with 2n = 24. Karyotype variation was found between populations of C. pallasii subsp. pallasii in Central Turkey and also in C. pallasii subsp. turcicus. [ABSTRACT FROM AUTHOR]

Crocus sativus is an autumn-flowering species, unknown as a wild plant but long-cultivated for its scarlet style branches which yield Saffron, the dye and flavouring agent. There are several naturally-occurring related species from southern Europe and south western Asia which form a natural group within the genus. C. niveus from Greece is similar to these morphologically and is included here but is less closely related. The characters of the group are defined, a key to the taxa is provided and their relationships discussed. [ABSTRACT FROM AUTHOR]

The Iserian Mts. form of Crocus vernus agg. has 2n = 16 and a karyotype clearly deviating from C. heuffelianus s. lat. [ABSTRACT FROM AUTHOR]

Western and eastern Carpathian populations of Crocus heuffelianus s. lat. (incl. C. scepusiensis) have 2n = 18 but differ in karyotype. While western populations are chromosomally monomorphic, eastern populations exhibit geographical karyotypic differentiation. [ABSTRACT FROM AUTHOR]